Quote:
Originally Posted by P-hack
Edit: only talking about induction motors here, I don't know much about PM/reluctance regen, other than it is gonna be putting out some volts weather you want it to or not in regen, so the top buck switch is probably needed there, but single variable slip seems easier to implement otherwise.
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We're on the same boat then.
The voltage rise on a PM is more contained than that on an IM as the rotor flux is constant and the generated emf is mainly dependent on the rotor speed.
With an IM flux is dependent on the slip as well. If the generated waveform commands a negative slip of enough amplitude the voltage shoots to an undefined value. And as the voltage boosts, more current flows into the motor. One needs a very fast voltage sampling similar to that used on dynamic bus ripple compensation, sampled at every PWM cycle.
That would ideally be achieved by the same micro as the motor control so that both are in sync.